#include "Systems/DescentCraft.h"
#include "Audio/DescentAudio.h"
#include "Core/DescentSimSubsystem.h"
#include "Debug/DescentStateRegistry.h"
#include "Player/DescentCharacter.h"
#include "Player/DescentPlayerController.h"
#include "Player/DescentVitals.h"
#include "Systems/DescentBuild.h"
#include "Systems/DescentCargo.h"
#include "UI/DescentHudSubsystem.h"
#include "UI/DescentUiSubsystem.h"
#include "Vehicles/DescentCarrier.h"
#include "Vehicles/KazahTender.h"
#include "Vehicles/TenderFlight.h"
#include "TheDescent.h"

#include "Engine/World.h"

namespace Descent::Craft
{
	FString ResName(int32 Res)
	{
		static const TCHAR* const Names[NumRes] = { TEXT("Ingot"), TEXT("Wafer"), TEXT("Lattice"), TEXT("Ferrite"), TEXT("Cobalt") };
		return Res >= 0 && Res < NumRes ? Names[Res] : TEXT("?");
	}

	const TArray<FRecipe>& Recipes()
	{
		static TArray<FRecipe> Table;
		if (Table.Num() > 0) { return Table; }
		auto Add = [](const TCHAR* Id, const TCHAR* Cat, const TCHAR* Name, const TCHAR* Desc, int32 I, int32 W, int32 L, int32 F, int32 C) -> FRecipe&
		{
			FRecipe R;
			R.Id = Id; R.Cat = Cat; R.Name = Name; R.Desc = Desc;
			R.Cost[Ingot] = I; R.Cost[Wafer] = W; R.Cost[Lattice] = L; R.Cost[Ferrite] = F; R.Cost[Cobalt] = C;
			return Table.Add_GetRef(R);
		};
		Add(TEXT("hull_reinforce"), TEXT("submersible"), TEXT("Hull Reinforcement"), TEXT("Tender hull x1.5"), 3, 0, 0, 0, 0);
		Add(TEXT("depth1"), TEXT("submersible"), TEXT("Depth Module Mk I"), TEXT("Rating 2,300 to 2,700 m"), 3, 2, 0, 0, 0);
		Add(TEXT("depth2"), TEXT("submersible"), TEXT("Depth Module Mk II"), TEXT("Rating to 3,150 m"), 0, 3, 2, 0, 0).Needs = TEXT("depth1");
		Add(TEXT("power2"), TEXT("submersible"), TEXT("Power Cell II"), TEXT("Capacity x1.7"), 2, 2, 0, 0, 0);
		Add(TEXT("thruster"), TEXT("submersible"), TEXT("Thruster Upgrade"), TEXT("Speed +25%"), 3, 0, 0, 0, 1);
		Add(TEXT("sonar_module"), TEXT("submersible"), TEXT("Sonar Module"), TEXT("Ping 260 m; flags honest voids red"), 0, 2, 0, 0, 0);
		Add(TEXT("drill2"), TEXT("mining"), TEXT("Drill Head Mk II"), TEXT("Radius +0.7 m, rate +50%"), 3, 0, 0, 0, 0);
		Add(TEXT("drill3"), TEXT("mining"), TEXT("Drill Head Mk III"), TEXT("Radius and rate again"), 2, 2, 1, 0, 0).Needs = TEXT("drill2");
		Add(TEXT("laser"), TEXT("mining"), TEXT("Laser Cutter"), TEXT("Alternative tool head (T)"), 0, 2, 1, 0, 0);
		Add(TEXT("suction2"), TEXT("mining"), TEXT("Suction Mk II"), TEXT("Range 22 m, pull 16"), 2, 0, 0, 0, 1);
		Add(TEXT("hold"), TEXT("mining"), TEXT("Hold Expansion"), TEXT("Every hold +8"), 3, 0, 0, 0, 0);
		Add(TEXT("hull_patch"), TEXT("carrier"), TEXT("Carrier Hull Patch"), TEXT("Carrier hull +25"), 4, 1, 0, 0, 0).bRepeatable = true;
		{ FRecipe& R = Add(TEXT("hand_sonar"), TEXT("explore"), TEXT("Handheld Sonar"), TEXT("Ping 90 m while swimming"), 1, 1, 0, 0, 0); R.Item = TEXT("hand_sonar"); R.ItemCount = 1; }
		{ FRecipe& R = Add(TEXT("flares"), TEXT("explore"), TEXT("Flares x5"), TEXT("Thrown lights, 120 s each"), 0, 0, 0, 2, 0); R.Item = TEXT("flare"); R.ItemCount = 5; R.bRepeatable = true; }
		{ FRecipe& R = Add(TEXT("beacons"), TEXT("explore"), TEXT("Marker Beacons x2"), TEXT("A marker on the map and the HUD"), 1, 0, 0, 0, 1); R.Item = TEXT("beacon"); R.ItemCount = 2; R.bRepeatable = true; }
		Add(TEXT("o2_high"), TEXT("explore"), TEXT("High-Capacity O2 Tank"), TEXT("90 s of air"), 2, 0, 0, 0, 0);
		Add(TEXT("o2_ultra"), TEXT("explore"), TEXT("Ultra O2 Tank"), TEXT("150 s of air"), 1, 1, 1, 0, 0);
		{ FRecipe& R = Add(TEXT("propulsor"), TEXT("explore"), TEXT("Sea-Glide Propulsor"), TEXT("Hold LMB: 7.5 m/s"), 2, 1, 0, 0, 0); R.Item = TEXT("propulsor"); R.ItemCount = 1; }
		auto Kit = [&Add](const TCHAR* Id, const TCHAR* Name, const TCHAR* Desc, int32 I, int32 W, int32 L) -> FRecipe&
		{
			FRecipe& R = Add(*FString::Printf(TEXT("kit_%s"), Id), TEXT("build"), Name, Desc, I, W, L, 0, 0);
			R.Kit = Id;
			R.bRepeatable = true;
			return R;
		};
		Kit(TEXT("locker"), TEXT("Storage Locker"), TEXT("+40 storage while placed"), 4, 0, 0);
		Kit(TEXT("rack"), TEXT("Box Rack"), TEXT("4 box slots"), 2, 0, 0);
		Kit(TEXT("arm1"), TEXT("Handling Arm Mk I"), TEXT("Reach 3.2 m, a box every 4.0 s"), 4, 2, 0);
		Kit(TEXT("arm2"), TEXT("Handling Arm Mk II"), TEXT("Reach 4.5 m, a box every 2.5 s"), 2, 2, 1).Needs = TEXT("kit_arm1");
		Kit(TEXT("light"), TEXT("Work Light"), TEXT("Wall or ceiling lamp"), 1, 0, 0);
		Kit(TEXT("table"), TEXT("Table"), TEXT("Furniture"), 1, 0, 0);
		Kit(TEXT("chair"), TEXT("Chair"), TEXT("Furniture"), 1, 0, 0);
		Kit(TEXT("shelf"), TEXT("Shelf"), TEXT("Furniture"), 1, 0, 0);
		Kit(TEXT("bunk"), TEXT("Bunk"), TEXT("Sleep anywhere"), 2, 0, 0);
		Kit(TEXT("couch"), TEXT("Couch"), TEXT("Furniture"), 2, 0, 0);
		Kit(TEXT("fabricator"), TEXT("Fabricator"), TEXT("A second fabricator"), 6, 2, 0);
		Kit(TEXT("refinery"), TEXT("Refinery"), TEXT("A second refinery"), 8, 3, 0);
		Add(TEXT("harpoon"), TEXT("weapons"), TEXT("Harpoon Sidearm"), TEXT("Tethys has not licensed weapons"), 0, 0, 0, 0, 0).bLocked = true;
		return Table;
	}

	const FRecipe* Find(FName Id)
	{
		for (const FRecipe& R : Recipes()) { if (R.Id == Id) { return &R; } }
		return nullptr;
	}

	bool Pay(const FRecipe& R, int32 Have[NumRes])
	{
		for (int32 I = 0; I < NumRes; ++I) { if (Have[I] < R.Cost[I]) { return false; } }
		for (int32 I = 0; I < NumRes; ++I) { Have[I] -= R.Cost[I]; }
		return true;
	}

	FString ItemName(FName Item)
	{
		if (Item == TEXT("flashlight")) { return TEXT("Flashlight"); }
		if (Item == TEXT("flare")) { return TEXT("Flare"); }
		if (Item == TEXT("beacon")) { return TEXT("Marker Beacon"); }
		if (Item == TEXT("hand_sonar")) { return TEXT("Handheld Sonar"); }
		if (Item == TEXT("propulsor")) { return TEXT("Sea-Glide Propulsor"); }
		return Item.IsNone() ? FString() : Item.ToString();
	}
}

namespace DC = Descent::Craft;

UDescentCraftSubsystem* UDescentCraftSubsystem::Get(const UWorld* World)
{
	return World ? World->GetSubsystem<UDescentCraftSubsystem>() : nullptr;
}

void UDescentCraftSubsystem::OnWorldBeginPlay(UWorld& InWorld)
{
	Super::OnWorldBeginPlay(InWorld);
	ResetAll();
	if (UDescentSimSubsystem* Sim = UDescentSimSubsystem::Get(&InWorld))
	{
		FDescentSimRegisterOptions Opt;
		Opt.Owner = TEXT("Craft");
		Opt.SubOrder = 30;
		StepHandle = Sim->RegisterStep(EDescentSimStep::Cargo, [this](const FDescentSimFrame& F) { Step(F.Dt); }, Opt);
	}
}

void UDescentCraftSubsystem::Deinitialize()
{
	if (UDescentSimSubsystem* Sim = UDescentSimSubsystem::Get(GetWorld())) { Sim->Unregister(StepHandle); }
	Super::Deinitialize();
}

void UDescentCraftSubsystem::ResetAll()
{
	Done.Reset();
	Slots.Reset();
	Slots.SetNum(24);
	for (FName& H : Hotbar) { H = NAME_None; }
	HotbarSelected = 0;
	PdaSelected = -1;
	// the suit starts with the flashlight in slot 1
	AddItem(TEXT("flashlight"), 1);
	Hotbar[0] = TEXT("flashlight");
}

int32 UDescentCraftSubsystem::Count(FName Item) const
{
	int32 N = 0;
	for (const FDescentItemStack& S : Slots) { if (S.Item == Item) { N += S.Count; } }
	return N;
}

bool UDescentCraftSubsystem::AddItem(FName Item, int32 N)
{
	if (Item.IsNone() || N <= 0) { return false; }
	for (FDescentItemStack& S : Slots) { if (S.Item == Item) { S.Count += N; return true; } }
	for (FDescentItemStack& S : Slots) { if (S.Item.IsNone()) { S.Item = Item; S.Count = N; return true; } }
	return false;
}

bool UDescentCraftSubsystem::RemoveItem(FName Item, int32 N)
{
	for (FDescentItemStack& S : Slots)
	{
		if (S.Item == Item && S.Count >= N)
		{
			S.Count -= N;
			if (S.Count == 0)
			{
				S.Item = NAME_None;
				for (FName& H : Hotbar) { if (H == Item) { H = NAME_None; } }
			}
			return true;
		}
	}
	return false;
}

bool UDescentCraftSubsystem::AssignHotbar(int32 Slot1to9, FName Item)
{
	if (Slot1to9 < 1 || Slot1to9 > 9 || (!Item.IsNone() && Count(Item) <= 0)) { return false; }
	for (FName& H : Hotbar) { if (H == Item) { H = NAME_None; } }   // an item sits in one slot only
	Hotbar[Slot1to9 - 1] = Item;
	return true;
}

void UDescentCraftSubsystem::GatherHave(int32 Have[DC::NumRes]) const
{
	const UDescentCargoSubsystem* Cargo = UDescentCargoSubsystem::Get(GetWorld());
	for (int32 I = 0; I < DC::NumRes; ++I) { Have[I] = 0; }
	if (!Cargo) { return; }
	for (int32 I = 0; I < 3; ++I) { Have[I] = Cargo->Refined[I]; }
	Have[DC::Ferrite] = Cargo->CountOre(0);
	Have[DC::Cobalt] = Cargo->CountOre(1);
}

bool UDescentCraftSubsystem::CanCraft(FName Id, FString* OutWhyNot) const
{
	auto No = [OutWhyNot](const TCHAR* Why) { if (OutWhyNot) { *OutWhyNot = Why; } return false; };
	const DC::FRecipe* R = DC::Find(Id);
	if (!R) { return No(TEXT("unknown recipe")); }
	if (R->bLocked) { return No(TEXT("Tethys has not licensed weapons")); }
	if (IsBuilding()) { return No(TEXT("The fabricator is building")); }
	if (!R->bRepeatable && Done.Contains(Id)) { return No(TEXT("Already installed")); }
	if (!R->Needs.IsNone() && !Done.Contains(R->Needs)) { const DC::FRecipe* N = DC::Find(R->Needs); return No(*FString::Printf(TEXT("Needs %s"), N ? *N->Name : TEXT("another module"))); }
	if (Id == TEXT("hull_patch"))
	{
		const ADescentCarrier* C = UDescentCarrierSubsystem::GetCarrier(GetWorld());
		if (!C || C->Helm.Hull >= 99.5) { return No(TEXT("The hull is not damaged")); }
	}
	int32 Have[DC::NumRes];
	GatherHave(Have);
	if (!DC::Pay(*R, Have)) { return No(TEXT("Not enough material")); }
	return true;
}

bool UDescentCraftSubsystem::Craft(FName Id, FString* OutWhyNot)
{
	if (!CanCraft(Id, OutWhyNot)) { return false; }
	const DC::FRecipe* R = DC::Find(Id);
	UDescentCargoSubsystem* Cargo = UDescentCargoSubsystem::Get(GetWorld());
	// the cost comes from storage and from the ore boxes
	for (int32 I = 0; I < 3; ++I) { Cargo->Refined[I] -= R->Cost[I]; }
	if (R->Cost[DC::Ferrite] > 0) { Cargo->ConsumeOre(0, R->Cost[DC::Ferrite]); }
	if (R->Cost[DC::Cobalt] > 0) { Cargo->ConsumeOre(1, R->Cost[DC::Cobalt]); }
	Done.Add(Id);
	++Crafted;
	BuildTimer = 2.0;
	ApplyOne(Id);
	if (UDescentAudioSubsystem* Audio = UDescentAudioSubsystem::Get(GetWorld())) { Audio->OneShot(TEXT("craft")); }
	if (UDescentHudSubsystem* Hud = UDescentHudSubsystem::Get(GetWorld())) { Hud->Model().PushToast(FString::Printf(TEXT("Built: %s"), *R->Name), EDescentHudToastKind::Good); }
	FillWindows();
	return true;
}

void UDescentCraftSubsystem::ApplyOne(FName Id, bool bFromLoad)
{
	const DC::FRecipe* R = DC::Find(Id);
	UWorld* World = GetWorld();
	if (!R || !World) { return; }
	if (!bFromLoad)
	{
		if (!R->Kit.IsNone()) { if (UDescentBuildSubsystem* Build = UDescentBuildSubsystem::Get(World)) { Build->AddKit(R->Kit, 1); } }
		if (!R->Item.IsNone()) { AddItem(R->Item, R->ItemCount); }
		if (Id == TEXT("hull_patch")) { if (ADescentCarrier* C = UDescentCarrierSubsystem::GetCarrier(World)) { C->Helm.Hull = FMath::Min(100.0, C->Helm.Hull + 25.0); } }
	}
	if (UDescentTenderFleet* Fleet = UDescentTenderFleet::Get(World))
	{
		for (const TWeakObjectPtr<AKazahTender>& W : Fleet->All())
		{
			AKazahTender* T = W.Get();
			if (!T) { continue; }
			Descent::Tender::FTenderUpgrades& U = T->Flight->Upgrades;
			if (Id == TEXT("hull_reinforce")) { const double Frac = T->Flight->HullHP / T->Flight->Stats().HullMax; U.HullMk = 1; T->Flight->HullHP = Frac * T->Flight->Stats().HullMax; }
			else if (Id == TEXT("depth1")) { U.DepthMk = FMath::Max(U.DepthMk, 1); }
			else if (Id == TEXT("depth2")) { U.DepthMk = 2; }
			else if (Id == TEXT("power2")) { U.bPowerCell2 = true; }
			else if (Id == TEXT("thruster")) { U.ThrustMk = 1; }
			else if (Id == TEXT("sonar_module")) { U.bSonarModule = true; }
			else if (Id == TEXT("drill2")) { U.DrillMk = FMath::Max(U.DrillMk, 1); }
			else if (Id == TEXT("drill3")) { U.DrillMk = 2; }
			else if (Id == TEXT("laser")) { U.bLaser = true; }
			else if (Id == TEXT("suction2")) { U.SuctionMk = 1; }
			else if (Id == TEXT("hold")) { U.HoldMk = 1; }
		}
	}
	if (Id == TEXT("o2_high") || Id == TEXT("o2_ultra"))
	{
		const APlayerController* PC = World->GetFirstPlayerController();
		if (ADescentCharacter* Ch = PC ? Cast<ADescentCharacter>(PC->GetPawn()) : nullptr)
		{
			const double Max = Done.Contains(TEXT("o2_ultra")) ? 150.0 : 90.0;
			Ch->Vitals->State.O2Max = FMath::Max(Ch->Vitals->State.O2Max, Max);
			Ch->Vitals->State.O2 = Ch->Vitals->State.O2Max;
		}
	}
}

void UDescentCraftSubsystem::Step(double Dt)
{
	if (BuildTimer > 0.0) { BuildTimer = FMath::Max(0.0, BuildTimer - Dt); }
	WindowTimer -= Dt;
	if (WindowTimer <= 0.0) { WindowTimer = 0.25; FillWindows(); }
	// the hotbar of the HUD: on foot and swimming
	UWorld* World = GetWorld();
	UDescentHudSubsystem* Hud = UDescentHudSubsystem::Get(World);
	const ADescentPlayerController* PC = World ? Cast<ADescentPlayerController>(World->GetFirstPlayerController()) : nullptr;
	if (Hud && PC)
	{
		FDescentHudModel& M = Hud->Model();
		M.bShowHotbar = PC->GetMode() == EDescentMode::Foot || PC->GetMode() == EDescentMode::Swim;
		// M10: the objective line says the next step of the loop
		const UDescentCargoSubsystem* Cargo = UDescentCargoSubsystem::Get(World);
		const AKazahTender* T = PC->GetTender();
		switch (PC->GetMode())
		{
		case EDescentMode::Sub: M.Objective = (T && T->Flight->HoldOrder.Num() > 0) ? TEXT("Dock: fly up under the moon pool, press E") : TEXT("Mine: LMB drill, RMB suction. R sonar"); break;
		case EDescentMode::Docked: M.Objective = TEXT("SPACE launch. E leave the Tender"); break;
		case EDescentMode::Helm: M.Objective = TEXT("Helm: mouse aims, W S lever. E leave"); break;
		case EDescentMode::Swim: M.Objective = TEXT("E at the pool ladder climbs out"); break;
		case EDescentMode::Foot:
			if (Cargo && Cargo->Carried()) { M.Objective = TEXT("Load the box into the refinery hopper (E)"); }
			else if (Cargo && Cargo->Boxes().Num() > 0) { M.Objective = TEXT("Carry the ore box from the packer to the refinery (E)"); }
			else if (Cargo && Cargo->StorageUsed() > 0) { M.Objective = TEXT("Refined goods: fabricator builds, terminal sells"); }
			else { M.Objective = TEXT("Sub bay: board a Tender (E)"); }
			break;
		default: M.Objective.Reset(); break;
		}
		M.HotbarSelected = HotbarSelected;
		M.Hotbar.SetNum(9);
		for (int32 I = 0; I < 9; ++I)
		{
			M.Hotbar[I].ItemId = Hotbar[I];
			M.Hotbar[I].Label = DC::ItemName(Hotbar[I]).Left(2).ToUpper();
			M.Hotbar[I].Count = Hotbar[I].IsNone() ? 0 : Count(Hotbar[I]);
		}
	}
}

void UDescentCraftSubsystem::OpenFabricator()
{
	UDescentUiSubsystem* Ui = UDescentUiSubsystem::Get(GetWorld());
	if (!Ui) { return; }
	Ui->Open(EDescentWindow::Fabricator);
	FillWindows();
}

void UDescentCraftSubsystem::FillWindows()
{
	UDescentUiSubsystem* Ui = UDescentUiSubsystem::Get(GetWorld());
	if (!Ui || !Ui->IsWindowOpen() || Ui->IsDemo()) { return; }   // the demo owns the models while it runs
	const EDescentWindow W = Ui->GetWindow();
	TWeakObjectPtr<UDescentCraftSubsystem> Weak(this);
	const UDescentCargoSubsystem* Cargo = UDescentCargoSubsystem::Get(GetWorld());
	const UDescentBuildSubsystem* Build = UDescentBuildSubsystem::Get(GetWorld());
	if (W == EDescentWindow::Fabricator)
	{
		int32 Have[DC::NumRes];
		GatherHave(Have);
		FDescentFabricatorViewModel& M = Ui->Models().Fabricator;
		M.Categories.Reset();
		for (const DC::FRecipe& R : DC::Recipes())
		{
			FDescentFabricatorCategory* Cat = M.Categories.FindByPredicate([&R](const FDescentFabricatorCategory& C) { return C.Id == R.Cat; });
			if (!Cat) { Cat = &M.Categories.AddDefaulted_GetRef(); Cat->Id = R.Cat; Cat->Label = R.Cat == TEXT("explore") ? FString(TEXT("EXPLORATION")) : R.Cat.ToString().ToUpper(); }
			FDescentRecipeRow Row;
			Row.Id = R.Id;
			Row.IconItem = R.Id;
			Row.Name = R.Name;
			Row.Desc = R.Desc;
			for (int32 I = 0; I < DC::NumRes; ++I)
			{
				if (R.Cost[I] > 0) { FDescentUiCost C; C.ItemId = FName(*DC::ResName(I).ToLower()); C.Name = DC::ResName(I); C.Need = R.Cost[I]; C.Have = Have[I]; Row.Costs.Add(C); }
			}
			FString Why;
			const bool bCan = CanCraft(R.Id, &Why);
			const bool bInstalled = !R.bRepeatable && Done.Contains(R.Id);
			Row.bLocked = R.bLocked || bInstalled || (!R.Needs.IsNone() && !Done.Contains(R.Needs)) || (R.Id == TEXT("hull_patch") && !bCan && Why.Contains(TEXT("damaged")));
			Row.LockedReason = Row.bLocked ? (bInstalled ? FString(TEXT("Installed")) : Why) : FString();
			Row.ButtonText = bInstalled ? TEXT("DONE") : TEXT("BUILD");
			const FName Id = R.Id;
			Row.OnBuild = [Weak, Id]()
			{
				UDescentCraftSubsystem* S = Weak.Get();
				FString Reason;
				if (S && !S->Craft(Id, &Reason)) { if (UDescentHudSubsystem* Hud = UDescentHudSubsystem::Get(S->GetWorld())) { Hud->Model().PushToast(Reason, EDescentHudToastKind::Warn); } }
			};
			Cat->Rows.Add(MoveTemp(Row));
		}
		M.BuildProgress = IsBuilding() ? static_cast<float>(1.0 - BuildTimer / 2.0) : 0.f;
		M.StatusText = IsBuilding() ? TEXT("Building") : TEXT("Ready");
		Ui->NotifyChanged();
	}
	else if (W == EDescentWindow::Pda)
	{
		FDescentPdaViewModel& M = Ui->Models().Pda;
		M.Slots.SetNum(24);
		for (int32 I = 0; I < 24; ++I)
		{
			M.Slots[I].ItemId = Slots[I].Item;
			M.Slots[I].Name = DC::ItemName(Slots[I].Item);
			M.Slots[I].Count = Slots[I].Count;
		}
		M.Selected = PdaSelected;
		const bool bSel = Slots.IsValidIndex(PdaSelected) && !Slots[PdaSelected].Item.IsNone();
		M.SelectedName = bSel ? DC::ItemName(Slots[PdaSelected].Item) : FString();
		M.SelectedDesc = bSel ? FString(TEXT("Press 1 to 9 to put it on the hotbar.")) : FString();
		M.O2Tank.ItemId = Done.Contains(TEXT("o2_ultra")) ? FName(TEXT("o2_ultra")) : (Done.Contains(TEXT("o2_high")) ? FName(TEXT("o2_high")) : FName(TEXT("o2_base")));
		M.O2Tank.Name = Done.Contains(TEXT("o2_ultra")) ? TEXT("Ultra O2 Tank") : (Done.Contains(TEXT("o2_high")) ? TEXT("High-Capacity O2 Tank") : TEXT("Standard O2 Tank"));
		M.O2Tank.Count = 1;
		M.OnSelect = [Weak](int32 I) { if (UDescentCraftSubsystem* S = Weak.Get()) { S->PdaSelected = I; S->FillWindows(); } };
		M.OnAssignHotbar = [Weak](int32 Slot)
		{
			UDescentCraftSubsystem* S = Weak.Get();
			if (S && S->Slots.IsValidIndex(S->PdaSelected) && !S->Slots[S->PdaSelected].Item.IsNone()) { S->AssignHotbar(Slot, S->Slots[S->PdaSelected].Item); }
		};
		Ui->NotifyChanged();
	}
	else if (W == EDescentWindow::Storage && Cargo)
	{
		static const TCHAR* const Names[3] = { TEXT("Ferrite Ingot"), TEXT("Cobalt Wafer"), TEXT("Pearl Lattice") };
		FDescentStorageViewModel& M = Ui->Models().Storage;
		M.Goods.Reset();
		M.Kits.Reset();
		for (int32 T = 0; T < 3; ++T) { M.Goods.Add({ Descent::Cargo::RefinedName(static_cast<uint8>(T)), Names[T], Cargo->Refined[T] }); }
		if (Build) { for (const Descent::Build::FKitDef& K : Descent::Build::Kits()) { if (Build->KitCount(K.Id) > 0) { M.Kits.Add({ K.Id, K.Name, Build->KitCount(K.Id) }); } } }
		M.Used = Cargo->StorageUsed();
		M.Cap = Cargo->StorageCap;
		Ui->NotifyChanged();
	}
}

// ---- state sections `inventory`, `upgrades` (section 9.4) ---------------------------------------------------------------

static FDescentStateProviderRegistrar GInventoryStateSection(TEXT("inventory"), [](UWorld* World, FJsonObject& Out)
{
	const UDescentCraftSubsystem* S = UDescentCraftSubsystem::Get(World);
	Out.SetBoolField(TEXT("available"), S != nullptr);
	if (!S) { return; }
	TArray<TSharedPtr<FJsonValue>> Slots, Bar;
	for (const FDescentItemStack& St : S->Slots)
	{
		TSharedRef<FJsonObject> J = MakeShared<FJsonObject>();
		J->SetStringField(TEXT("item"), St.Item.IsNone() ? FString() : St.Item.ToString());
		J->SetNumberField(TEXT("count"), St.Count);
		Slots.Add(MakeShared<FJsonValueObject>(J));
	}
	for (const FName& H : S->Hotbar) { Bar.Add(MakeShared<FJsonValueString>(H.IsNone() ? FString() : H.ToString())); }
	Out.SetArrayField(TEXT("slots"), Slots);
	Out.SetArrayField(TEXT("hotbar"), Bar);
	Out.SetNumberField(TEXT("hotbar_selected"), S->HotbarSelected + 1);
	Out.SetNumberField(TEXT("flares"), S->Count(TEXT("flare")));
	Out.SetStringField(TEXT("weapon_slot"), TEXT("NOT LICENSED"));
});

static FDescentStateProviderRegistrar GUpgradesStateSection(TEXT("upgrades"), [](UWorld* World, FJsonObject& Out)
{
	const UDescentCraftSubsystem* S = UDescentCraftSubsystem::Get(World);
	Out.SetBoolField(TEXT("available"), S != nullptr);
	if (!S) { return; }
	TArray<FName> Names = S->Done.Array();
	Names.Sort(FNameLexicalLess());
	TArray<TSharedPtr<FJsonValue>> List;
	for (const FName& N : Names) { List.Add(MakeShared<FJsonValueString>(N.ToString())); }
	Out.SetArrayField(TEXT("done"), List);
	Out.SetNumberField(TEXT("count"), Names.Num());
	Out.SetBoolField(TEXT("building"), S->IsBuilding());
});